Dead Wind, fixed

[BobbyA]

Had a strange one today, car started as normal, drove the 16 miles to work, no issues.
However when I came to start it this afternoon, the car wouldn't unlock with the key, opened the door manually, put the key in ignition, nothing !!
Not even a light on the dashboard, strangely both the horn and the dashcam worked (runs of 12v socket), and I know the battery is good.

After much head scratching and looking on Renault forums, the twingo 133 forum suggested, disconnect the earth terminal from the battery for 10 minutes, so I did this and bingo it worked !!
It's a reset for the ECU, I'm going to get my mechanic to run a diagnostic check, but hopefully it's a one off incident.

[pittstop]

Too many electronics in these modern cars!!  

I had a problem with my lights. 

I unwittingly cured it; a bit like your solution of disconnecting the battery; by pulling all the lighting fuses which forced the "lighting ECU" to reset itself & work properly.

I didn't even know the lights were controlled by a mini computer; I just thought that it was via simple physical switches; but was advised by a main dealer that that was the case.

Pity I'd already wasted £140 on a new lighting switching unit!!

Glad you are back in action.